Embodiments of the present invention relate to hand held computer systems. More particularly, embodiments of the present invention provide a method and apparatus for controlling a communication port in response to receiving location information.
Communication ports on hand held computer systems, particularly when configured for driving signal lines over distances greater than approximately five centimeters, are relatively high power devices within a battery powered hand held computer system. For example, well known driver electronics to convert from CMOS logic levels to RS-232 voltage levels can consume as much power as the main processor in the hand held system. Because of the limited amount of power in the system""s battery, it is therefore important to keep the communication port inactive, in a low power state, whenever possible.
Unfortunately, in prior art methods and systems, an application needing location information (e.g., a moving map display) would turn on a communication port and establish a communications dialog with the location determining device, e.g., a Global Positioning System device. The application would typically poll the device for updated information. This process would continue, and the communication port would unfortunately remain open in its highest power mode, for the duration of the application""s session. This results in an unnecessary power drain, and shortens the battery life of such a hand held computer.
Further, while the application was communicating across the communication port, the communication port was unavailable to other applications that may have also needed to communicate across the communication port. For example, if a travel guide application was also available on the system, it would be unable to access the communication port, and consequently would be unable to access the location information required for its operation. Such limitations restricted the effectiveness of prior art hand held computer systems.
In addition, it was generally necessary for application programs to be constructed specifically for a particular location determining device, because each GPS device vendor typically has a unique communications format. For example, software vendor xe2x80x9cAxe2x80x9d was required to make application program version xe2x80x9cA1xe2x80x9d to work with GPS device xe2x80x9cB,xe2x80x9d and application program version xe2x80x9cA2xe2x80x9d to work with GPS device xe2x80x9cC.xe2x80x9d This is a result of the prior art implementation of the application program communicating directly with the location determining device. Creating and managing such software variations for GPS units from many suppliers is a heavy burden for software vendors. Unfortunately, it is also problematic for users of the hand held device, as they must be aware of interoperability requirements. A major goal of usability is to shield the user from such technical concerns.
Consequently, improvements in the management of a communication port offer improvements in battery life and effectiveness of hand held computer systems, and are highly desired by manufacturers and users alike.
Therefore, it would be advantageous to provide a method and apparatus to provide for intermittent use of a port in response to location information pushed by a location determining device. A further need exists for a method of sharing a communication port. A still further need exists for a method of distributing location information among several applications. A need further exists for providing information to applications of a hand held computer system in a general or universal format understood by all applications.
Embodiments of the present invention provide a method and system for intermittent use of a port in response to location information pushed by a location determining device. Embodiments of the present invention provide a method and system that allow for sharing a communication port. Embodiments of the present invention provide a method and system for distributing location information among several applications. Embodiments also employ a universal data format for distributing location data to applications, thereby obviating the need for the applications to be aware of any unique or specific GPS interface.
A method and apparatus for receiving data via the intermittent use of a port is disclosed. One embodiment of the preset invention may first access a signal from a location determining device. Responsive to the signal, a communication port may be automatically activated. Location information may then be received via the communication port. Responsive to the reception of the information, the communication port may be automatically deactivated. Application programs that have registered or requested location information may be notified of the receipt of location information.
Another embodiment of the present invention provides for the location information to be generated by a Global Positioning System.
In one embodiment of the present invention, the communication port is substantially compliant with RS-232.
In another embodiment of the present invention, the communication port is substantially compliant with a Secure Digital card interface.
In yet another embodiment of the present invention, information may be received via a communication port in a format unique to the location determining device. The information may be determined to originate from a Global Positioning System device. Responsive to such a determination, the information may be translated into a universal data format recognizable to several applications. The several applications may be notified that GPS information is available.
In still another embodiment of the present invention, location information may be received from a mobile telephony device.